Resilient filler for tires



Patented Jan.. Ril, ll..

JAMES l. DAIJBEY, OF ELGFI, ILINOIS.

RESlIlIENT FILLEBl FOR TIRESr Application filed February 6,1922. Serial No. 534,295.

object being to pro-vide affilier which shallf under use, assume a predetermined form for best supporting the imposed load.` The fillers of my invention are especially adapted `foruse in place of or inllieu of the well, known pneumatic tubes in pneumatic tires for automobiles.

rlhis present invention is an improvement upon my earlier invention described and claimed in United States Patent i No. 1,351,894, issuedto ine September 7, 1920.

Pneumatic tires` andnespecially the casing for such tires are so ormedand constructed that when theair `pressure yin the tire is properly proportioned to Ithe load, the distortion of the road` contacting portion oit the tire is suitably proportionedftothe size of the tire to attain the best results in cushioningl and Wearing qualities.`

In replacing the fair tube with aiillei of spongy rubber, it is desirabley as a final result, to retain the formu ofv cross section at the contacting part or" the4 tire under the load as originally designed. It will be understood thatk at the `time ka rubber sponge filler is placed in a casing itl is designed to be compressed in the casingto a pressure substantially the same as would be used with air in a similar casing.. It will, be understood that under load, that is inuse, the

casiiigandiiller are more or less distorted,v

being of course shortened radially and thickenedtransversely.. IY ind that ythe rubber1 sponge filler does not fully return to its `standstill at about ten percent reduction of the radial depth of the filler. To overcome this objection and to provide a tire which will, under Working conditions.y finally result in a shape best adapted to the conditions of operation, l have conceived the idea of making the filler originally oi va shape Which ivill allow it` to befformed in- Wardly by the operating road pressure in practical use, the amount which l have found the filler and casing will linally be the desired shape. c

Instead of making the filler of substantially circular cross-section to fit Within the casing,` l elongate it radially, making it `of substantially equal crossfsectional area but of a diilierent shape. As the elongation is reduced in use, the transversevvidth is increased until lina-lly it `is substantially circular. in section invit-s permanent load bearing iorm. At this time,ythe filler still retains nearly if not fully, its original elasticityand the casing is maintained in substantiall its true circular cross-sectional form. n `the above discussion of my invention l have considered thewniain portion of the. filler, not the inner part which eX- tends between the beaded edges ot the casing, such inner part obviously conforming with the space between the inner edges ol: the casing. i

For a complete understanding` of my invention `reterenceis made to the accompanying drawings forming part oi? this specification, and `in ivhich:- i

Figure 1 a fragmentary side elevation of a tire shown partly in section and made in accordance with my invention;

FigureQ isa radial cross-section of the tire shown mounted on a rim and in its final or Working condition;` `i

Figure 3 is a radial section of the tire ller, shoivingin full lines its iorm when first inserted in` the casing and in dotted lines in its form after ithas reached its final form by use on the road; and

`Figure l1 is a detail cross-sectional view of theivedge or keyfloclcportion ot the filler.

In said drawings 1` illustrates a tire casing such as is in common use lor pneumatic tires. The form shoivn is of the clincher type and in Figures 1 and 2 is shown as mounted upon a clincher rim Q, the tire being provided with base beads 3 fitting within the hooked Hanges 4 ot' the rim. .lt will be obvious that my invention is equally use- "i'ul in connection with other forms of casings and rims.

In Figure 2 l". have shown the casing 1 in `this effect to be and so that ivheirtliis occurs its normal shape such as it would be held in, it an inner tube were used with the proper amount of air pressure within the tube. My improved filler comprises a spongy rubber ring 5 and a Wedge ring 6 of the same material. Preferably as shown and described, in my said patent, the main portion 5 of the iiller is provided with a slot 7 at its inner periphery `lor receiving the wedging member 6. rIhe two parts together are so proportioned as to cross sectional area that when they are inclosed in the casing and the casing is properly mounted on the rim, the casing will be held distended with substantially the same pressure as though it were provided with a pneumatic tube and the proper air pressure was held within the tube.

As explained hereinbefore, the spongy rubber of which the iller is composed is compressed under road pressure and does not have sutiicient resiliency in its form as originally made and mounted in the casing to regain its original shape.

However, I have discovered that there is a limit to this permanent distortion and after use upon the road of two or three thousand miles the distortion of the filler reaches this limit. After this limit has been reached, the normal distortion of the part in contact with the ground is overcome during the revolution of the tire and the cross-sectional shape, of the filler and consequently of the tire, is substantially permanent, the incidental compression ot the filler at the point of road contact being merely temporary.

In order to have the tire in what might be termed its true normal shape after the filler has thus been formed by road use, I make the liller oil larger dimensions radially to begin with than I desire it to be permanently. In other words, the radial dimension a Figure 3 is greater than the radial dimension` e Figure 3 by the amount b Figure 3 which the filler is compressed in use. Likewise, the transverse dimension c of the filler Figure 3 is less than the linal transverse dimension c Figure 3 of the iiller in its final form. The crossesectional area of the filler is substantially the same at all times but its shape is varied from original torni to its iinal form.

I have found that with allowing substantially one-tenth decrease in the radial dimension of the liller, I am enabled to attain the result of a filler and easing of normal dimensions and avoid a. final liattening ot the tire which has been the common condition of such filled tires where the liller was originally produced in conformity with the normal shape and size of the casing.

While it is possible that other modiieations ot my invention will be suggested to those skilled in the art, I do not limit or confine my invention to the specific i'orin and construction of liller herein shown and described.

I claim:

l. A yielding resilient filler for a. tire casing, having a normal shape for use, the filler having original dimensions greater radially and less transversely than the normal inside dimensions of the casing and adapted in use to be reduced radially and enlarged transversely, and for the purpose specified.

2. A yielding resilient liller tor a tire easing, the filler adapted to be enclosed within a casing under a pressure substantially the same as though the casing were used with a pneumatic tube, the filler being of a larger radial dimension and a smaller transverse dimension than the similar normal inside dimensions of the casing and adapted in use to be reduced in its radial dimension and increased in its transverse dimension to cause the easing to iinally assume its norma l, shape.

3. In a yielding resilient filler for tire casings, a main ring-lile liller having a. slot at its inner edge in combination with a wedging member adapted to be `inserted in the slot, the two parts composing a filler of suitable cross-sectional area .in relation lo a casing 'in which it is to be used to produce Signed at Chicago, Illinois, this 2nd day ot February, 1922.

JAMES Il'. DALBIC Y. 

